This kind of filter attaching apparatus is, for example, capable of producing a double filter cigarette by aligning a filter plug having the length equal to two filters with cigarettes to form an intermediate product of a double filter cigarette and winding a tip paper piece around the intermediate product. Specifically, the filter attaching apparatus comprises rotating drum trains for forming and conveying the intermediate products. The filter attaching apparatus further comprises a roll of tip paper and draws out a tip paper web from the roll. Paste is applied to one side of the tip paper web in the drawing process thereof, and then the tip paper web is cut into tip paper pieces on a rotating drum or a receiving drum. The tip paper piece is adhered to the intermediate product on the paste-applied side thereof at the position where the drum train for conveying intermediate products faces the receiving drum, and wound around the outer circumference of the intermediate product by the rolling movement of the product in a rolling passage. The rolling passage is defined, for example, between the receiving drum and a rolling plate. When the intermediate product is fed into the rolling passage, that is, the intermediate product is transferred from the drum train onto the rolling plate, the intermediate product is rolled between the rolling plate and the receiving drum in the feeding direction of tip paper pieces. In this manner, the winding of the tip paper piece connects the filter plug and two cigarettes and forms a double filter cigarette. Thereafter, the double filter cigarette is cut at the center thereof into two filter cigarettes.
In recent years, the conveying speed of intermediate products tends to be made higher and higher in order to improve the productivity of filter cigarettes. As a result, the rotational speed of the drum train for conveying intermediate products also becomes greater, and a considerable inertia acts on cigarettes when the intermediate products are transferred between drums or when the products are carried in the rotating direction of the drums. The inertia causes shredded tobacco, fine particles of thereof, etc. to fall off the cigarettes. As a result, the rotation of the drum scatter the shredded tobacco and the fine particles to form the atmosphere of shredded tobacco and fine particles around the periphery of the intermediate products. If the shredded tobacco or fine particles are deposited on the outer surface of the filter plug or the paste-applied side of the tip paper piece in the atmosphere, the shredded tobacco or fine particles are caught between the tip paper piece and the intermediate product. Once there occurs such intrusion of the shredded tobacco or fine particles, the subject filter cigarettes make defective products, and then every one of them have to be removed.
For this reason, in the technical field of filter attaching apparatus, it is required to prevent defective products of filter cigarettes from being produced due to the intrusion of the shredded tobacco or fine particles thereof, and to realize the prevention is one of the objects of the present invention.